The system of creating floating slabs by means of distributing metallic containers in welded wire fabric in the form of hollow cubes that are within the forging is known. The raising phase occurs once the concrete has set, and mechanical accessories in the form of shock-absorbing elements are positioned in the hollow interiors of the holders which are coupled under beveled ribs that are located in two of the corners thereof. In this way, the raising of the floating slab will be achieved to the extent desired by means of the pressure of the shock absorbers in its upper part.
The welded wire fabric is usually formed by two mesh structures, each of which are created by wires that intersect one another at right angles, forming grids, whose points of contact are joined by welding. These are positioned superimposed, trying to align the grids of the two meshes for the correct insertion of holders which have a height equal to the height of the slab containing the welded wire fabrics, and are positioned within the interstices of the two meshes, so that, after the setting of the concrete, the meshes are closely aligned in the slab. For this purpose, a plurality of metallic rods are installed welded on the surface of each holder in the horizontal direction which protrude from their structure. In fixing to the rebar, in order to avoid the displacement thereof in the pouring phase of the concrete, once in the grid, the rods are fastened to the welded wire fabric by means of wires. This involves a lot of work for the operator in the positioning and a limited rigidity of the system, causing the holders to move when the concrete is poured or by the operator's own movements within the rebar. If the setting occurs with any of these elements displaced or twisted, there will be a weak zone at this point which may cause the fracture of the floating slab in the raising phase.
The grid of the welded wire fabric is produced by having different proportions. The prior-art system has the drawback that the rods welded to the structure of the holder are arranged so that they overlie the grid in every case, to facilitate its bundling by means of wire. For this the operator usually has problems at the time of fitting the holder in the welded wire fabric, and has to shorten the rebar to make a suitable cavity in the mesh to receive he holder. Apart from the labor-intensive work that it involves, it results in a structure that is hazardous to the work zone. Where the ends of the rods are welded together, and where the cuts made in the rebar result in many sharp points, thee is a risk to the operator in the work of positioning the wires or merely by the operator's being situated on the structure.
The welded wire fabric is manufactured in different extension dimensions for the different positioning sites. For this, the bonding of one surface of the welded wire fabric with those surfaces which follow it in the work is necessary. It is equally necessary to anchor the corners of the layers of the welded wire fabric, if a worker or operator goes through zones remote from the center, and creates a force on one or both of the layers, this force then causes the structure to rise.
Another type of element is known for positioning shock absorbers in the forging that is made up of a metallic cylinder with walls of considerable size, within which the shock absorber is arranged, having two horizontal projections in its contour for being situated in the rebar. The complexity of this structure makes the manufacture thereof very expensive, and the securing in the welded wire fabric, in spite of the weight that it has, is insufficient.